Description

I'm running the latest VBOX 1.5.4 on Ubuntu 7.10 (Gutsy) 64-bit version. On a Quad Core Intel Q6600 processor. My guest OS is Win XP SP2 using NAT in the VBox Network Settings.
When I do something VERY network intensive on the guest OS such as running a port scanner or proxy scanner for more than a few minutes, the Virtual Machine core dumps (aborts), and I get the following log:

This is a known problem with NAT on 64-bit hosts. The problem is that slirp (the NAT engine VirtualBox is using) is not 64-bit clean. Our hack to work around this problem is obviously not sufficient...

Yes, this would help. Or use host interface networking + bridging, see the user manual. Unfortunately, host interface networing is kind of broken in 1.6.0 but we hope that we can release a bugfix release soon (I cannot explain anything as always).

Could you please let us know whether there is the bug fix for host interface networking for 1.6.0 and how to get it and install? Also maybe you have some news about the original NAT problem. Thank you!

Host networking is already fixed in SVN and 1.6.2 (which contains the fix) will be out very soon. The NAT problem is still not fixed. This problem only occurs on 64-bit hosts. As I stated above, we are using the slirp code which has some limitations. We plan to fix this but this will take some more time.

The priority of this ticket doesn't matter. We started a big networking overhaul some time ago which will fix this issue among others. Unfortunately, there is no workaround. This bug only happens on AMD64 hosts and only with NAT (buggy slirp engine).

I have the same problem as I mentioned above, but fortunately there is a workaround at least for my specific situation. Since the host interface networking was repaired I have used it in the following way:

I've created a new virtual interface vbox0 and told the VirtualBox to use it.

Then I have added special rules to iptables to actually enable NAT.

As you probably already noticed I didn't bother with bridge creation. As a result I have NAT working, but also I can forward ports if I need to. And it didn't require additional real IPs or any other changes to host network configuration.

Yes, that is a good idea. Use host interface if possible as this interface currently better performs than NAT and it has no known bugs (in contrast to NAT). Perhaps you would like to write some text for our wiki. There is no public write access but I would delighted to put your text on the Wiki pages. But perhaps some of your ideas are already written in either

You are right - it's not that hard to do such networking and parts of the process are already described in various sources. I will try to explain what I did and maybe it will serve as a simple HOWTO.

In my specific case I am using Ubuntu 8.04 AMD64, my regular Internet connection is via PPP. In the VirtualBox help there is a clear and detailed description of how a virtual network adapter could be added and how to use it in host interface networking. So after it is done I have the following network configuration:

The vbox0 is the new virtual adapter. The ppp0 is the tunnel, which is opened when I connect to my provider. Then I have set my VM network card to have 172.16.0.2 IP address and 172.16.0.1 as a default gateway. I have set its DNS the same way as it is set on my host system.

I forgot to add - when you will be reading the VirtualBox manual (menu help -> contents -> virtual networking -> Host Interface Networking and bridging on Linux hosts) you will need only the part related to the virtual interface creation (you don't have to specify bridge name here)

sudo VBoxAddIF vbox0 <user>

then set an IP address for the interface and then tell VM to use it (done via virtual machine settings). So, once again, you don't have to create bridge for it.

I'm sorry for the last post, I was just trying to help resolve the bug.

I wasn't sure if this qualifies as a new Bug, but I got the same error, using Host interface netwoking type, with bridge, and doing the NAT outside VBox, with iptables on host machine. Could the bug apply to any heavy network activity and not just NAT one?